I have a feeling the motor was stuck at TDC when youve been trying to start the motor. The motor must be un-stuck before trying to crank it any method or the weak point will break and the crank and rod arent going anywhere anytime soon.

I have to do the same with my STS motors on my starter box or the rubber wheel will wear quickly. Get it un-stuck then start it , otherwise you will break stuff.

On my old cv-r long time ago. I had to sometimes take the motor completely apart and tap down the piston with a wooden dowell on a paper towell. I would never try to unstick a motor with a pull-start or especially rotostart.

You cant even get them to barely move via the flywheel and a wrench. So I can only imagine what a small roto gear or pull-start is taking.

STS motor is tight , heat it up with hairdryer and loosen glow-plug for the first start of the day and make sure its completely not stuck. It should turn over fairly easy then without broken pull-start cords and rotostarts.

Its a new motor which is the hardest time on starting components. Afterwards it will be fine if you use the precautions.

Hey Guys the motor turned over once or twice before the gears turned to dust. I do not believe that I am dumb whan it comes to rc. Yes I am a rookie but No dummie. I do apprechate all of the help from you guys. I did have the glowplug loose. If I loosen it anymore I will have to just remove it. I am not nocking the sts I believe that its an awesome motor I just think it has some bugs that needs to be worked out. Like the starting system. today I will try the hpi gear and let you know how that worked. Thanks again.

Dino, maybe you can explain on your instructions that you need to removed the shims AFTER breaking, I went to break mine in and I didn't know if i had to removed them before or after, I had to come here and ask. Most people might know but now newbies....like me!
just trying to help out.
Great engine i have to say!

Because he hasnt added on extra shims and therefore you wont need to do that. He is just explaining that he should add extra shims to allieviate the hard starting but then people wont know what to take out after break-in.

I don't get it. I have never had a pullstart break. Ever. My .28m was crazy tight when new, I could pick up my truck if not careful. And mine is HEAVY.
I rate this engine as a 10. My old rb was not this nice at $300.00.

Pullstarts are an item that is easily abused. That's why they don't last. As Dino said, this is a race-level engine. The compression when new is crazy. No pullstart will take hard yanks of the cord. I say way to go STS!! I wish my past engines were this nice, especially for what I spent on them.

Dino: Maybe a more serious caution should be added to the instructions.

ozpall: My instructions have shim recommendations. Do the new ones not have that?? (not sarcastic) The instructions do not say "after beak-in change to this" and maybe they should.

Thank you for all suggestions.....without your suggestions we can't make it better.....

Theres nothing to change. Just shim it for whatever fuel % you run in the instructions.

I would like to add my experience to date with this motor. I broke in as instructions said with no problems.... I experienced a broken pull start spring shortly after breaking in engine. This promted me to fit my roto start back plate purchased with engine.... the small gear in the roto start backplate broke 3 teeth so I removed and replaced pull start.... this second pull starter also broke within first tank of fuel.. just refused to return in.. pulled off and inspected turned out that the knott on the rope ring had split the plastic and caused it to wedge in its housing.... Thats when I realised that the gear from HPI roto backplate fitted and has worked fine to date... I also use a cordless drill with low torque setting now..... if it is possible to find another of these engines when this one expires.... I will not hesitate to buy again.... even with the starting issues.....

I wish there was more availability here in New Zealand.... I wish I could sell and promote them here as R/C nitros are rare here in NZ... yet all that see mine really are interested...

GOOD WORK STS

we have shipped them as far as Poland. So New Zealand shouldn't be a problem. www.racernine.com

mine says to use 3mm with 20% and 4mm with 30% fuel, so i'm running 20% i got to run 3mm, Do i take 1mm off before break in or after? that was my Q, I know now to do it after but at first i didn't so im sure there would be more people with more q. like this.

Hello people. After reading alot of this thread i bought an sts .28 as my nitrostar 25 crank case SNAPPED on a heavy impact landing up the wronge way on concrete. Today i have been running it in and am very impressed, but i have a big problem. The thread for the glow plug has stripped with little force tightening the plug and now i have fuel pissing out when it is running. Can anyone tell me if i have to get another sts button or will another make fit. As you can imagine it has fustrated me and i dont know where to get sts parts. Any advise will be much appreciated. Thanks.

Two posts above yours.. http://www.racernine.com/sts28.html

The thread must of cross threaded? if there is any resistance when starting the thread stop and try again.

we have the head button for the older two piece head design and the new one peice button/cooling head design in stock

Thanks, would the two piece design be better as the one piece seems very soft unless mine had a fault, also after stripping the engine down i found only one copper head shim, is that right?
cant wait to get it working again i had run about 6 tanks of fuel through my savage with the new engine without touching the mixture settings and and it was starting to wheelie when changing into second gear even though it had fuel pissing out of the head and tonnes of smoke coming out of the exhaust. the gear ratio i am using is 18/47, AMAZING.

P.S. i live in the U.K. how much would the parts be to ship here?

you have a pm